Club Kasino [message #20023] |
Mon, 20 January 2014 15:23 |
Mic Ferad
Messages: 7 Registered: January 2014 Location: NJ
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Junior Member |
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I'm new to the forum.
Got a Club Kasino from my brother. The tremlo doesn't work. The green wire in the reverb pan was off, so I soldered it back on. You can barely hear reverb on 10. Wondering if anyone has suggestions on where to start. I'm not afraid to pull out the scalpel so bring it on.
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Re: Club Kasino [message #20026 is a reply to message #20023] |
Tue, 21 January 2014 07:41 |
stevem
Messages: 4773 Registered: June 2004 Location: NY
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Senior Member |
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Thanks Pleat!
Well if thats the case I will hopefully assume right that the amp uses a PC303 board.
In these amps a foot switch is only needed to turn a effect off, so maybe someone got inside and jumped out the section of the foot switch for the tremolo.
Even when these amps have tremolo circuit problem, if the switch jack has not been messed with, you will still hear some very small amount of tremolo effect if the intensity is cranked!
In regards to the reverb, if you find your pan is shot, Antique electronics has replacements in the Mod line of pans.
You need a type 4F with a input impeadance of 1475 and a output impeadance 2250.
They may offer a choise of two different ones, one with a long decay and one with a medium, I find that unless I will every play surf music, that the medium sutes me best for guitar.
[Updated on: Tue, 21 January 2014 07:44] Report message to a moderator
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Re: Club Kasino [message #20039 is a reply to message #20023] |
Thu, 23 January 2014 06:45 |
stevem
Messages: 4773 Registered: June 2004 Location: NY
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Senior Member |
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In regards to the 5129 pc schematic, our site does not list it in the tech section and I myself do not have one.
Maybe Pleat or Bill on this site do however and we can then pin down what you need in regards to a replacment reverb pan?
Once Fender got bought out by CBS and got into the penney pinching silverface era of amps the wiring layout when to hell and they had to place many small value tone sucking caps to tame the oscilation problems that some of these amps had due to this relaxed QC level.
In those days you could get one given Fender amp from a production run and it would be fine and need the tone sucking caps,while the very next one had a issue!
This is not to mention that they also switched over to the brown epoxy coulping caps that test quite poor for ESR, which this in and of itself could make any circuit oscilate.
Why they chose in 76 to stay with these poor sounding caps, yet blow the bucks on going to UL type output transforms in even the guitar amps is a question that I would love to hear the story about the thought process that led to it!!
Just to offer up a example of the lack of QC, I have what must be many 1976 pro reverb amps ( 2 output tubes) that was made with a output transformer for a ( 4 output tube)twin reverb amp!
I pickedup this amp from the original owner who was never really fully happy with the amp, no wonder as it only put out 35 watts of RMS power when it sould have had 68.
Fender`s rating of these amps being 75 RMS is not true.
Here`s a classic example of how to mis- manage a company, CBS buys fender for 13 mill and then ends up having to sell it off due to poor sales for 1 mill less than the purchase price, at a time when the other top amp manufactures products where selling well!
[Updated on: Thu, 23 January 2014 07:19] Report message to a moderator
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Re: Club Kasino [message #20040 is a reply to message #20039] |
Thu, 23 January 2014 13:13 |
chicagobill
Messages: 2006 Registered: April 2003
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Senior Member |
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I found the schematic at the Music Electronics Forum site. In the Schematic Requests section, there is a Kustom section with a number of schematics for the later model boards.
The first thing that I always check is the reverb tank wires that connect the transducer coils to the RCA jacks inside the pan. These are very thin wires and break all of the time. They can break in an obvious way or they can break at the end where they connect to the coil. In any case, inspect them carefully and see if they are still solidly connected.
As Steve posted earlier, this is a high impedance tank and there should be approximately 50-200 ohms across the input coil and 200 ohms across the output coil. The RCA input jack shield must be isolated from the chassis.
The reverb/trem circuit uses elements from three different ICs. The input to the FX is driven by 1/2 of the 739 chip. The trem effect is created by the 80848 chip and the reverb tank is driven by 1/2 of the 5558 chip. The other half of the 5558 chip is used for the trem effect low frequency oscillator.
If the circuit is passing a clean signal and the reverb and trem do not work, the first thing that I would test would be the 5558 chip, as it is part of both FX circuits.
Do you have the ability to measure voltages while the amp is turned on and running?
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Re: Club Kasino [message #20045 is a reply to message #20023] |
Thu, 23 January 2014 22:50 |
chicagobill
Messages: 2006 Registered: April 2003
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Senior Member |
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The pan readings sound correct. Is the amp humming? If not then, leave the caps alone.
What is rusted on the resistor?
What you need to do with the amp turned on, is to measure dc voltages in the amp circuits. If you don't feel comfortable doing that then you could just try replacing the 5558 chip. It may or may not cure the problem.
If you want to try and measure the voltages, just be certain to stay away from the ac circuits. The dc voltages are low enough that you won't hurt yourself, but you can do damage to the amp if you are not carfeful.
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Re: Club Kasino [message #20049 is a reply to message #20023] |
Fri, 24 January 2014 11:43 |
chicagobill
Messages: 2006 Registered: April 2003
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Senior Member |
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There is no opamp in the return circuit, there is just a single transistor stage.
Steve PM your email to me and I'll send the schematic to you.
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